Apparatus for purging crystal massecuites



v 1933- c. J. COPLAND ET AL 1,928,831

APPARATUS FOR PURGING CRYSTAL MASSECUITES.

Filed Aug. 20, 1930 3 Sheets-Sheet 1 Oct. 3, 1933. Q J. op ETAL 1,928,881

APPARATUS FOR PURGING CRYSTAL MASSECUITES Filed Aug. 20, 1930 5 Sheets-Sheet 2 e fj s- 19' 50 110*- ufih 51 M imc 1933- c. J; COPLAND ET AL 2 APPARATUS FOR PURGING CRYSTAL MASSECUITES Filed Aug. 20, 1930 3 Sheets-Sheet 3 Patented Oct. 3, 1933 UNITED STATES PATENT OFFICE APPARATUS FOR. PURGING CRYSTAL M ssEoUrrEs ware Application August 20, 1930. Serial No. 476,636

Claims. (Cl. 210-67) This invention relates to the purging of crystal massecuites, more particularly dextrose massecuites, of their mother liquor, by means of centrifugal machines or other machines for extract- 5 ing the mother liquor from the solid sugar.

One of the objects of the invention is to provide an apparatus for washing the sugar, after' most of the mother liquor has been extracted therefrom, to remove, by displacement, the

residual mother liquor incapable of being removed by centrifugal force or other force directly exertedon the liquid. 4

-In accordance with this invention, the sugar is given two washes, the first with sweet water,

that is water containing some mother liquor and possibly dissolved sugar, and the second with fresh water. Preferably the sweet water is wash water, derived from the second or fresh water washing of a previous batch or batches of sugar.

By this method, the melting of the crystals is minimized (which is of particular importance in the case of dextrose crystals, and more especially in the case of crystals of dextrose hydrate which dissolve readily in fresh water but less so, naturally, in sugar solution). The washing is also accomplished with less water than when fresh water only is used and a more concentrated wash liquor is discharged from the purging machine.

The sweet water used for the first wash, because of its viscosity, is more effective in removing the residual mother liquor from the sugar than fresh water. Fresh water is, however, necessary to remove the last traces of impurities from the sugar, that is to displace the sweet water.

A further object is to provide an apparatus, which shall be largely automatic in its operation, for carrying out the above described method and particularly an apparatus for (1) controlling the application of the sweet water and fresh water 49 to sugar; and '(2) directing the discharged liquids into their proper channels.

A preferred form of apparatus is disclosed in the accompanying drawings, wherein Fig. 1 is a diagrammatic view in elevation of two centrifugal machines arranged and provided with appurtenances for practicing the invention.

Fig. 2 is a view in elevation of one of the centrifugal machines, with associated mechanisms, this view being 180 from the view of Fig. 1 and on a larger scale.

Fig. 3 is a fragmentary plan view of the machine shown in Fig. 2.

Fig. 4 is a view in elevation, with parts broken away, of the valve and valve actuating mechanism for controlling the introduction of washing liquids into and the discharge of the same from the centrifugal machine.

Fig. 5 is a sectional plan on line 5-5 of Fig. 4.

Fig. 6 is a vertical sectional view on line 6-6- 6 r Fig. 4. 0

Fig. 7 is a fragmentary view corresponding to Fig. 6, but with the screw actuated follower out of engagement with the controlling screw; and

Fig. 8 is a side elevation of the controlling mechanism to show-particularly the mechanism for controlling the discharge of liquors from the centrifugal machine.

Referring first to Fig. 1, A and B designate two centrifugal machines forming part of a battery of such machines, of whatever number the factory may require. C designates a trough or other conduit, common to all of the centrifugal machines, for receiving mother liquor and'also liquids from the first washes to which the sugar in the centrifugals is subjected. D is a sweet water conduit for receiving liquids from the second washes, and E a tank into which this conduit discharges. F is a sweet water supply pipe, provided with a pump 10, for delivering sweet water, through branch pipes 11 and 12,- to the centrifugals A and B. G is a fresh water pipe having branches 13 and 14 leading to the centrifugals A and B, respectively. The centrifugals are provided with discharge conduits H, each provided witha tilting bucket or switching device J for directing the discharged liquids either to the mother liquor trough C or the sweet water trough D. In this figure the troughs C and D are shown one below the other, for complete illustration of the process, while in the remaining figures they are shown side by side at the same level. Each centrifugal machine is provided with a controllin'g mechanism K which operates, when set, to first-after a timed interval topermit the extraction of most of the mother liquor by centrifugal forceopen and close the valve in the sweet water pipe F and then open and close the valve. in the fresh water pipe G. This same controlling apparatus releases the tilting bucket or switching member J (which has been previously set to discharge into the mother liquor conduit C) so that the bucket tilts into position to direct the liquids from discharge conduit H into the sweet waterconduit D. This operation takes place in timed relation with the valve controls so that the sweet water from the second or fresh water wash is delivered to conduit D and thence into tank E for re-use in subsequent first washes.

The mechanism for controlling the application no of the wash liquids to the sugar is as follows:

Referring now to Figs. 1, 5, 6 and 7, a yoke member 15 is supported on the shell of the cen trifugal machine and carries the valve casings 16, 17 to which lead the sweet water branch pipe 11 (reference being made to the controlling apparatus on the centrifugal A) and the fresh water branch pipe 13 respectively. Discharge pipes 18 and 18 lead from the valve casings to a common spray nozzle pipe 19 (Fig. 3) which extends into the basket of the centrifugal machine.

Reciprocating valves are arranged in the valve casings 16 and 17, valve 20 in valve casing 17 being shown in Fig. 6. These valves have depending stems 21, 21, provided at their lower ends with cam shoes 22, 23. The shoes 22, 23 are successively engaged by a threaded cam follower 24 which engages a screw 25 on a shaft 26 mounted to rotate in the yoke 15 and provided at the end toward which the follower 24 moves with a smooth portion 27.

The follower 24 is provided with a collar 28 engaging a rod 29, the ends of which are fixed in the yoke 15, the follower being thereby slidable and pivoted upon this rod so that it may be moved away from shaft 26 and its screw 25 for resetting. With this in view the follower is provided with a handle 30. In order to insure a definite interval of time before the follower comes into contact with the shoe 22 to permit the extraction of most of the mother liquor, a stationary stop member 31 is provided and the follower 24 is provided with a stop lug 32, which moves inside a rib 33 on the stop member 31 when the follower is tilted back (Fig. '7) to reset it. The

stop member 31 is arranged on a rod 34 fixed in the yoke 15 and. is formed with a recess 35 opposite the end of the screw 25 which permits the follower to be rocked to engage the screw only when the follower reaches the end of the sliding movement on rod 29, such rocking movement being prevented so long as the lug 32 stands in front of rib 33.

The mechanism for controlling the discharge of the liquids from the centrifugal machines is as follows:

The switching device J comprises a bucket having gudgeons 36, 37 (Fig. 3) pivoted in cross members 38 on the troughs C, D. The gudgeon 37 is provided with a crank 39 connected by a link 40 with an arm 41 fixed to a vertical shaft 42 guided in keepers 43 on the outer shaft 44 of the centrifugal machine. Fixed to the upper end of shaft 42 is an arm 44 adapted to be engaged by a hook 45 (Figs. 3 and 8). The hook 45 forms part of a rocking member 46, the ends 47, 48 of which are pivoted on a rod 49 (Fig. 4) extending across the yoke 15. The member 46 is formed with a longitudinal slot 50 (Fig. 5) for an adjustable cam member 51 secured to member 46 by the bolt 52. This cam member 51 is arranged to be engaged by the follower 24 after the follower has passed the shoe 22 on stem 21 of the sweet water valve and before it has engaged the shoe 23 on the other valve stem. The engagement of the follower with cam 51 rocks member 46 to release the hook 45 from arm 41, whereupon the weight 53 on the bucket J (Fig. 2) causes the bucket to tilt, so as to direct the liquid outfiowing through the chute H into the sweet water trough D.

Rsum of operation: At the beginning of the centrifuging of a batch of massecuite the follower 24 is set in engagement with the left hand end of the screw 25, as shown in Figs. 4 and 5, and the arm 44 is engaged with thehook 45 which causes the bucket J to direct outfiowing liquids through H into the mother liquor trough C. The centrifugal machine is set in operation and shaft 26 being driven (in any suitable manner, not shown) the movements that follow are automatic. After the follower 24 has moved along the screw 25 a period suflicient to permit the bulk of the mother liquor to be extracted by centrifugal force from the sugar and discharged through chute H into the mother liquor trough C, the follower 24 engages theshoe 22 on the stem of the sweet water valve and sweet water is injected into the centrifugal machine from pipe F. This continues until the follower 24 rides away from shoe 22. The follower next engages the cam 51, causing the release of arm 44 by hook 45 and bucket J is tilted by weight 53 so as to direct outflowing liquors to the sweet water trough D. The follower then engages the shoe 23 controlling the fresh water valve, (an interval of time elapsing, preferably, after the sweet water valve is closed before the fresh water valve is opened, to permit extraction of as much sweet water from the sugar as can be extracted by centrifugal force alone) and thereupon fresh water is injected into the centrifugal machine from pipe G. The fresh water valve is closedwhen the follower rides away from the shoe 23. Shortly after this the follower runs off screw 25 over the smooth portion 27 of the shaft. The pu ged sugar is then discharged from the centrifug machine, in the usual manner, a fresh charge of massecuite introduced and the follower and bucket J reset for the new series of operations.

It is the intention to coverby patent all modifications of apparatus within the scope'of the appended claims, together with known and recognized equivalents, While the invention is described as applied to centrifugal machines, the same principles of operation and control may be applied to purging machines of other types.

We claim:

1. In apparatus for purging crystal massecuites, the combination with a purging machine of sweet water and fresh water supply pipes provided with no reciprocating valves, a revoluble screw, and a threaded follower adapted to engage-said screw adapted to impart opening and closing movements to first one of said valves and then the 12 other.

, 2. In apparatus for purging crystal massecuites, the combination with a purging machine of sweet water and fresh water supply pipes provided with reciprocating valves, a revoluble screw, and a threaded follower engaging said screw adapted to impart, opening and closing movements to first one of said valves and then the other,'said follower being pivoted so as to be movable away from the screw for resetting the same on the screw.

3. In apparatus for purging crystal massecuites, the combination with a purging machine of sweet .water and fresh water supply pipes provided with reciprocating valves, a revoluble screw and a threaded follower engaging said screw adapted to impart opening and closing movements to first one of said valves and then the other, said screw having a smooth portion at the end toward which the follower travels.

4. In apparatus for purging crystal massecuites, the combination with a purging machine of sweet water and fresh water supply pipes provided with reciprocating valves, 9. revoluble screw, and a threaded follower engaging said screw adapted to impart opening and closing movements to first one of said valves and then the other, said follower being pivoted so as to be movable away from the screw ifor resetting the same on the screw, a stationary stop member and a stop member on the follower arranged to permit the follower when reset to be engaged with the screw only at the extremity of the screw.

5. In apparatus for purging crystal massecuites comprising a purging machine, sweet water and fresh water supply pipes provided with valves having depending reciprocating stems formed with shoes, a revoluble screw, and a threaded cam follower-on said screw adapted to engage said shoes one after another.

6. In apparatus for purging crystal massecuites comprising a purging machine having a discharge conduit, a mother liquor conduit, a sweet water conduit, sweet water and fresh water supply pipes provided with reciprocating valves, a switching member to direct the liquid in the discharge conduit either to the mother liquor conduit or the sweet water conduit, a revoluble screw and a threaded follower adapted to actuate the movements of said valves and switching member.

7. In apparatus for purging crystal massecuites comprising a purging machine provided with a discharge conduit for liquids, sweet water and fresh water supply pipes provided with valves, a mother liquor conduit, a sweet water conduit, 21. pivoted switching member adapted to be engaged to direct liquor in the discharge conduit to the mother liquor conduit and weighted so that when released it directs liquors into the sweet water conduit, a screw and a follower for the screw adapted to open and close first the sweet water valve and then the fresh water valve, and between said operations to release the switching member.

8. The combination with a purging machine having a discharge conduit, means for introducing first sweet water and then fresh water into said machine, a mother liquor conduit, a sweet water conduit, a switching member for directing the liquid from the discharge conduit either into the mother liquor conduit or the sweet water conduit, a revolving screw, a threaded follower, and means actuated by the follower for controlling the movements of said switching member.

9. In combination with a purging machine having a discharge conduit, means for introducing first sweet water and then fresh water into said machine, a mother liquor conduit, a sweet water conduit, a pivoted switching member weighted so that it tends to be rocked to position to direct liquids from the discharge conduit into the sweet water conduit, mechanism for rocking said switching member to direct discharged liquids into the mother liquor conduit comprising a lever, and a hook to engage said lever arm, and a screw and threaded follower for rocking the hook to release said lever arm.

10. In combination with a centrifugal machine having a discharge conduit for liquid, fresh water and sweet water supply pipes provided with valves having a depending stem provided with shoes, a tilting bucket weighted so as to be tilted to direct liquids from the discharge conduit into the sweet water conduit, mechanism comprising a lever arm and a pivoted hook for holding said bucket in position to direct discharged liquids into the mother liquor conduit, an actuating screw, and a follower adapted to first open and close the mother liquor valve, then release said hook from said arm and then open and close the fresh water valve, said follower being pivoted so that it may be rocked away from said screw for resetting.

CHARLES J. COPLAND. WILLIAM B. NEWKIRK. 

